/*
 * crc_ccitt.c
 *
 *  Created on: May 6, 2020
 *      Author: layst
 */

#include "kl_crc.h"
#include "shell.h"

namespace Crc {

static const uint16_t CRCTable[256] = {
        0x0000,0x1021,0x2042,0x3063,0x4084,0x50A5,0x60C6,0x70E7,0x8108,0x9129,0xA14A,0xB16B,0xC18C,0xD1AD,0xE1CE,0xF1EF,
        0x1231,0x0210,0x3273,0x2252,0x52B5,0x4294,0x72F7,0x62D6,0x9339,0x8318,0xB37B,0xA35A,0xD3BD,0xC39C,0xF3FF,0xE3DE,
        0x2462,0x3443,0x0420,0x1401,0x64E6,0x74C7,0x44A4,0x5485,0xA56A,0xB54B,0x8528,0x9509,0xE5EE,0xF5CF,0xC5AC,0xD58D,
        0x3653,0x2672,0x1611,0x0630,0x76D7,0x66F6,0x5695,0x46B4,0xB75B,0xA77A,0x9719,0x8738,0xF7DF,0xE7FE,0xD79D,0xC7BC,
        0x48C4,0x58E5,0x6886,0x78A7,0x0840,0x1861,0x2802,0x3823,0xC9CC,0xD9ED,0xE98E,0xF9AF,0x8948,0x9969,0xA90A,0xB92B,
        0x5AF5,0x4AD4,0x7AB7,0x6A96,0x1A71,0x0A50,0x3A33,0x2A12,0xDBFD,0xCBDC,0xFBBF,0xEB9E,0x9B79,0x8B58,0xBB3B,0xAB1A,
        0x6CA6,0x7C87,0x4CE4,0x5CC5,0x2C22,0x3C03,0x0C60,0x1C41,0xEDAE,0xFD8F,0xCDEC,0xDDCD,0xAD2A,0xBD0B,0x8D68,0x9D49,
        0x7E97,0x6EB6,0x5ED5,0x4EF4,0x3E13,0x2E32,0x1E51,0x0E70,0xFF9F,0xEFBE,0xDFDD,0xCFFC,0xBF1B,0xAF3A,0x9F59,0x8F78,
        0x9188,0x81A9,0xB1CA,0xA1EB,0xD10C,0xC12D,0xF14E,0xE16F,0x1080,0x00A1,0x30C2,0x20E3,0x5004,0x4025,0x7046,0x6067,
        0x83B9,0x9398,0xA3FB,0xB3DA,0xC33D,0xD31C,0xE37F,0xF35E,0x02B1,0x1290,0x22F3,0x32D2,0x4235,0x5214,0x6277,0x7256,
        0xB5EA,0xA5CB,0x95A8,0x8589,0xF56E,0xE54F,0xD52C,0xC50D,0x34E2,0x24C3,0x14A0,0x0481,0x7466,0x6447,0x5424,0x4405,
        0xA7DB,0xB7FA,0x8799,0x97B8,0xE75F,0xF77E,0xC71D,0xD73C,0x26D3,0x36F2,0x0691,0x16B0,0x6657,0x7676,0x4615,0x5634,
        0xD94C,0xC96D,0xF90E,0xE92F,0x99C8,0x89E9,0xB98A,0xA9AB,0x5844,0x4865,0x7806,0x6827,0x18C0,0x08E1,0x3882,0x28A3,
        0xCB7D,0xDB5C,0xEB3F,0xFB1E,0x8BF9,0x9BD8,0xABBB,0xBB9A,0x4A75,0x5A54,0x6A37,0x7A16,0x0AF1,0x1AD0,0x2AB3,0x3A92,
        0xFD2E,0xED0F,0xDD6C,0xCD4D,0xBDAA,0xAD8B,0x9DE8,0x8DC9,0x7C26,0x6C07,0x5C64,0x4C45,0x3CA2,0x2C83,0x1CE0,0x0CC1,
        0xEF1F,0xFF3E,0xCF5D,0xDF7C,0xAF9B,0xBFBA,0x8FD9,0x9FF8,0x6E17,0x7E36,0x4E55,0x5E74,0x2E93,0x3EB2,0x0ED1,0x1EF0,
};

uint16_t CalculateCRC16(uint8_t *Buf, uint32_t Len) {
    uint16_t crc = CRC_INITVALUE;
    for(uint32_t i=0; i<Len; ++i) {
        crc = (crc << 8) ^ CRCTable[(crc >> 8) ^ (0xFF & Buf[i])];
    }
    return crc;
}

void InitHw() {
    RCC->AHBENR |= RCC_AHBENR_CRCEN;
    CRC->CR = (0b01 << 3); // poly sz = 16
    CRC->POL = 4129;
}

uint16_t CalculateCRC16HW(uint8_t *Buf, uint32_t Len) {
    CRC->INIT = CRC_INITVALUE;
    // Calculate
    while(Len--) *(volatile uint8_t*)&CRC->DR = *Buf++;
    return (uint16_t)CRC->DR;
}

#if defined STM32L4XX

const stm32_dma_stream_t *PDma;

void InitHWDMA() {
    RCC->AHBENR |= RCC_AHBENR_CRCEN;
    CRC->CR = (0b01 << 3); // poly sz = 16
    CRC->INIT = CRC_INITVALUE;
    CRC->POL = 4129;
    PDma = dmaStreamAlloc(STM32_DMA_STREAM_ID(1, 1), IRQ_PRIO_LOW, nullptr, nullptr);
}

#define CRC_DMA_MODE (STM32_DMA_CR_CHSEL(1) | DMA_PRIORITY_HIGH | \
        STM32_DMA_CR_MSIZE_BYTE | STM32_DMA_CR_PSIZE_BYTE | STM32_DMA_CR_PINC |\
        STM32_DMA_CR_DIR_M2M | STM32_DMA_CR_EN)


uint16_t CalculateCRC16HWDMA(uint8_t *Buf, uint32_t Len) {
    CRC->CR |= CRC_CR_RESET;
//    dmaStreamSetPeripheral(PDma, Buf);
//    dmaStreamSetMemory0(PDma, &CRC->DR);
//    dmaStreamSetTransactionSize(PDma, Len);
//    dmaStreamSetMode(PDma, CRC_DMA_MODE);
//    dmaWaitCompletion(PDma);
    return CRC->DR;
}
#endif

void CCITT16_PrintTable() {
    uint16_t poly = 4129;
    uint16_t temp, a;
    uint32_t Cnt = 0;

    for(uint16_t i = 0; i < 256; ++i) {
        temp = 0;
        a = (uint16_t)(i << 8);
        for(uint16_t j=0; j < 8; ++j) {
            if(((temp ^ a) & 0x8000) != 0) {
                temp = (uint16_t)((temp << 1) ^ poly);
            }
            else {
                temp <<= 1;
            }
            a <<= 1;
        }
        Printf("0x%04X,", temp);
        if(Cnt++ == 15) {
            Cnt = 0;
            Printf("\r");
        }
    }
}

} // namespace
